Pontoon flotation apparatus



M. MULICK PONTOON FLOTATION APPARATUS July 11, 1950 2 Sheets-Sheet 1Filed March 28, 1945 k WM m m M.

ATTOR/VfK July 11, 1950 M. MULICK -PONTOON FLOTATION APPARATUS 2Sheets-Sheet 2 Filed March 28, 1945 HVVENTUR. Mfchcle/ Mu/fck W uQL JXPatented July ll 1950 UNITED STATES PATE N or ce PONTOON FLOTATIKONAPPARATU Michael Mulick, United States Navy Application March 28, 1945Serial N 0. 585,3'l0

6 Claims. (01. 114-54) (Granted under the act of Mara; 3', 1883 asamended April 30, 1928;370'OQ G.'757) need for pontoon flotationapparatus that is rigid, strong, light and formed of multiple cells andthat can be individually filled with as, such as air, or emptied.Strength and rigidity are essential to withstand the severe stresses encountered in both military and civilian operations as well as to providethe desired shape to the apparatus. Because of the need for rapidly andfrequently being transported from place to place it is essential that aminimum of weight and bulk be embodied and that the apparatus be adaptedfor complete disassembly. Multiple cells are necessary to insure that aleak occurring in any cell causes only local failure and will notresultin complete failure as would be the case with asingle cell. A furtheradvantage in multiple cells is that by proper selection of theindividual cells that are'filled with air and those that are emptied itis possible to orient the apparatus relative to other objects whenfloating or submerged in the water.

An object of the invention therefore is to provide pontoon flotationapparatus having an open framework of steel members that give a maximumof strength and rigidity and a minimum of weight and bulk and thedesired shape to the construction.

It is also an object to provide an apparatus having multiple cells thatcan be individually filled or emptied of air.

A further object is to-provide a novel cell construction for pontoonflotation apparatus having an internal bladder of rubber or similarexpansible material that can be inflated to fill the -cell or collapsedto occupy only a part of the space within the cell together with aspring or other resilient suspension means for supporting the bladderwithin the cell whereby the bladder is protected from shock or injurycaused by jarring of the cell frame and whereby proper orientation ofthe bladder within the cell is insured regardless of whether the bladderis in collapsed or inflated condition.

A further object is to provide a lining of netlike material inside thecell walls to form an envelope into which the bladder expands wheninflated, such lining protecting the bladder from I 2 byagenciesexterior to the cell, strengthening the bladder when inflated,and serving as the cell wall in the interstices within the latticeworkof the frame and thus eliminating the need for solid steel cellwalls. and thereby greatly reducing the weight and bulk of theapparatus;

In the accompanying drawings: Y Fig. 1 illustrates a. preferred form ofthis iii- .vention comprising a pontoon having, forjexample, nineindividualcells and is partly broken away for clarity of illustration. AFig. 2 isa detailed view illustrating the manner in which the net liningfor each cell is attached to the metal framework and furtherillustrating the method by which the bladder .is suspended within eachcell. l y

Fig. 3 illustrates a form of the invention in which the pontooncomprises a single cell.

Fig. 4 illustrates the use of a pontoon embodying this invention inraisin a sunken ship. I Fig. 5 illustrates the use of a pontoonembodying this invention in forming a floating bridge,

Fig. 1 shows a preferred form of pontoon as embodying a latticeframework ll having horizontal strips l2, interconnecting end strips I 3and vertical; strips l4. These strips are made of .steel or othersuitable material and formed from angles, fiat, strips or any desiredcross sectional shapes. The framework defines multiple cells, forexample, nine individual cells Ill, each of which is generally cubic inshape, though other shapes may be used. The strips forming the frameworkare fastened together by bolts or any other securing means suitable forallowing rapid and complete disassembly for packing and shipment. Theframework strips are spaced relatively widely apart to form a latticehavinglarge interstices.

The lattice framework is thus rigid, stron'gand of whatever shape isdesiredand because of the large interstices'in the lattice it is lightin weight and of minimum bulk when dismantled. j At the top left of Fig.1 is a breakaway revealin the construction of a single cell Ill in thepontoonand at the top right ofthis 'view is a breakaway showing. thelattice framework H of a single cell '10. Inside each cell'is a bladder[5, which canbe made of rubber or other material impervious ,to air andwhich is adapted upon inflation to fill the cell completely while onlypartly filling the cell. when deflated. The shape of the bladder can'beadapted to fit best the shape of the cell and with a cubic cell abladderof cubic shape is suitable.

vabrasion against the cell walls and from injury .The bladderisresiliently supported within the 3 cell by shock springs 16, each ofwhich is attached at one end to the bladder and at the other end to asuitable point on the frame. Other resilient means can be used in placeof the springs if desired. In using a cubic bladder and cell it isdesirable to provide a shock spring at each corner of the bladder .forattachmentto-the adjacent corner'of the cell frame: In Fig; '2 is shownan enlargement of one shock spring mounting. An anchor pad I1 isprovided. at the 1 corner of the bladder and one endof the spring issecured to it, the other endbeingsecuredto a bracket l8 at the corner ofcell frame-H. "These shock spring mounts protect the bladder againstdamage when pontoon framel'l is subjected-to severe jarring or shock.The spring mounts-.-.alsow insure proper positionin of the bladder,within the cell, regardless of whether-sit is inflated .or collapsed.

A lining is is withineach cell to cover the cell ,walls'. Thislining I9is of net-like -or-woven fabrication andany suitable material can be"used. In Fig. 2 is shown an enlargement of the manner in which thelining can be fastened to each cell wall I. Along its edge the lininglg'can be clamped between frame H and clamping strip 20 and secured inplace by suitable fasteners 2|. Lining l9 forms a resilient envelope,into which bladder 15 expands when inflated, and serves to protectbladder 15 from abrasion against the metal strips of theframe H and fromdamage 'by' external agencies. Lining l9 further'serves -as-the cellwall in the large openings of the frame latticework ll, thus eliminatingthe need for a 'solid steel wall with consequent reduction in weight toa minimum, but without sacrificing strength and rigidity.

The'combination of widely spaced frame members II in cell in and liningl9 within'cell- It! produces several advantagesnot found motherconstructions. It is the frame 'members i l and lining l9 together thatform the cell-wall and this-affords a construction-that incorporates-the"rigidity, strength and'shape-giving characteris- =.tics-of a steelconstruction with the lightness in :eight" resulting from use of anet-'likeliningand elimination of need for solid steel walls.Further,-there is a minimum of'bulk-when-the pon- *toon is dismantledandpacked for shipment because the steel'strips offrame l can be-compactlypacked for 'shipment'in contrast to the bulk of solid steel plates;These features make the' pontoon ideal for-use where a strong, rigid;light-construction is desired'andfurther make the pontoon ideal for'work where frequent 'andrapid dismantling and shipmentffrom P13081130place is required.

A hose 22 is connected with eachicellby a fittin 23 whereby air .orothersuitableigasnan be used to inflate or deflate bladder l5. Brackets flarefor securing the hoseto framework ll. Hoses from the various cellsaresecuredtogether 'bymanifold block 25.

In Fig. 3 is shown a modifiedformpfmy invention wherein the pontooncomprises a single cell Ill of construction similar to the celll'lldescribed in connection with'Fig. 1. "In this form .of th'e invention,framework Tl l 'is:provided:'with fittings 26 that can be used. forattaching'thefcell to other cells of similar construction whereby acomposite pontoon of the desired size can "be built up.

In Fig. 4 is shown the use .of the invention in raising a sunken ship..Brackets zT-arewelded or otherwise attached to the hull or the vesselto be raised. Pontoons 28 embodying the present invention are thensecured to the brackets by lashings 29 or other suitable means. Whensubmerged in the water prior to raising the ship,

5 bladders l5 in the pontoon are deflated to provide a minimum ofdisplacement and buoyancy. To raise the vessel bladders .15 .of the.pontoon are inflated and the increased displacement and buoyancy floatthe ship.

' Because the pontoon is formed of multiple cells ill .thatcanbeindividually inflated and deflated, a, leak in any particular cell [0results in localized ,iai'lurezonly-and results not in complete failure,as would be the case if only a. single cell were "rs-used. Themultiplecells have the further advantage :that by controlling cells ll)individually when inflating anddeflating it is possible to controlthepontoon and its orientation in the water. For example, it is possible tolash the pontoon over thetop of a relatively small sunken object,and'theninraising-by controlling cells'lilindividually; to causeinversion of the pontoon and object 'so'that when brought to thesurface-of the water the object "is on top of'the pontoon.-

In Fig. 5 isshown a further useof the pontoon in forming a floatingbridge; A depression in the earth is shown at 39 together with a body ofwater at'3l. ,A pontoon embodying the present invention floats at '32 onthe water-and gangways 33 span the gap frompontoon to shore.

Variousrnodifrcations and changes can be' made in the above withoutdeparting from the spirit andscope of this invention as set forth' inthe appended claims.

- The inventiondescribedherein may be manufactured and used by or-iorthe Government of the Unitedstates of America-tor governmental purposeswithout-thepaymentof any royalties "thereon or therefor. 40. What isclaimedis:

l. Flotation "apparatus having a frame formed from a lattice ofrelativelywidely spaced-metal strips and definingindividual cellseachprovided with a lining of fabric :materialwhich serves as the cellwall in the relatively large interstices between the metal strips,a"bladder-within -each cell adapted for inflation and'defiation-meansfor inflating and defla'tingsaid bladden-andresil- "ient means "forretaining the bladder in proper slr'position 'withinieach cell.

'2. "Flotation, apparatuscomprisin'g a single-cell formed from-a latticeof relatively widely spaced metal strips, a lining of fabricmaterial'withinthe cell and serving ,as the cell wallin'therelativelylarge intersticesbetween themetal strips, an expansiblebladder-'withinthecell adapted tofillthe cell when inflated and toonly'partially fillthe cell when deflated, resilient-means for-attachingthe bladder to the n'ietallattice, means' for inflating and-deflatingthe bladder, andfittingsfior securing the'cellgto othe'r cellsofsimilarconstruction wherebya composite apparatus of desired size and shape maybe formed.

'3. Flotation apparatus suitable for use inmarine' salvage andengineering operations having a frame of relatively Widely spaced steelstrips defining multiple cells of generally cubic hape, a rubber bladderof generally cubic shape within each cell adapted to fill the cell wheninflated and .to only partly'fill the 'cell'when deflated; a spring forattaching each corner-of the bladder to the adjacent corner of the'cellirame to retain the bladder in position within the cell regardlessof whether inflated OrJdeflated, a 'liriing of'net material-within eachcell adapted-t0 form-the 5 cell wall in the relatively large intersticesbetween the steel strips of the frame and adapted further to serve as aprotective envelope into which the bladder expands when inflated, hosemembers leading into the bladders whereby inflation and deflation of thebladder may be expected, said apparatus being adapted for completedisassembly to facilitate packing and shipment.

4. Flotation apparatus comprising a substantially rigid frame, a bladderadapted to be infiated and collapsed within said frame, and resilientmeans for positioning said bladder in predetermined and substantiallyfixed position within said frame in inflated and collapsed condition.

5. Flotation apparatus comprising a rigid 15 frame, an elastic bladderadapted to be inflated and collapsed within said rigid frame, andresilient means between said frame and said bladder for positioning saidbladder in predetermined and substantially fixed position within saidframe in 2 inflated and collapsed conditions.

6. Flotation apparatus comprising a substantially rigid lattice framedefining a cell, a lining in said frame forming the cell wall in thelattice interstices, an elastic bladder adapted to be infiated andcollapsed within the cell, and resilient means between said frame andbladder for positioning said bladder in predetermined position in thecell in inflated and collapsed condition.

MICHAEL MULICK.

REFERENCES CITED The following references are of record in th file ofthis patent:

UNITED STATES PATENTS Number Name Date 317,274 Amiro May 5, 18851,253,526 Portella Jan. 15, 1918 1,332,433 Deam Mar. 2, 1929 1,384,094Salinger July 12, 1921 1,430,957 Diamantides Oct. 3, 1922 1,486,131Dutton Mar. 11, 1924 1,691,738 Powell Nov. 13, 1928 2,320,288 Margolinet a1. May 25, 1943 2,374,372 Moss Apr. 24, 1945 2,411,649 Brizay Nov.26, 1946

